Inflammatory and Autoimmune Aspects of Multisystem Inflammatory Syndrome in Children (MIS-C): A Prospective Cohort...

Area of Science:

• Immunology
• Pediatrics
• Infectious Diseases

Background:

• Multisystem Inflammatory Syndrome in Children (MIS-C) is a serious COVID-19 complication.
• The underlying immune mechanisms driving MIS-C severity remain unclear.

Purpose of the Study:

• To compare immune biomarkers between children with MIS-C and those with moderate-severe COVID-19.
• To identify immune molecules contributing to MIS-C development.

Main Methods:

• Analysis of clinical samples from hospitalized children with COVID-19 or MIS-C.
• Enumeration of blood leukocytes and measurement of serum cytokines, chemokines, antibodies, and autoantibodies.

Main Results:

• MIS-C patients showed higher neutrophil/lymphocyte and eosinophil/lymphocyte ratios.
• Elevated IgM and IgA to SARS-CoV-2 RBD, and higher levels of type-2 cytokines (IL-4, IL-5, IL-6, IL-8, IL-10, IL-13, IL-33) were observed in MIS-C.
• Increased IgG autoantibodies to brain antigens, pentraxin, and anti-caspr2 were found in MIS-C patients.

Conclusions:

• Type-2 inflammation and autoantibody production may play a role in MIS-C pathogenesis.
• Autoimmune responses could contribute to the severe manifestations of MIS-C in some children.
• Further research is needed to elucidate triggers of autoimmunity and type-2 inflammation in MIS-C.